U.S. patent number 5,604,407 [Application Number 08/553,190] was granted by the patent office on 1997-02-18 for method and device for controlling vehicle interior lighting.
This patent grant is currently assigned to Mercedes-Benz AG. Invention is credited to Rudolf Andres, Benno Forstner, Dieter Freerichs, Helmut Grickscheit, Reinhold Mickeler, Volker Petri, Armin Staehle.
United States Patent |
5,604,407 |
Andres , et al. |
February 18, 1997 |
Method and device for controlling vehicle interior lighting
Abstract
A method and device for controlling vehicle interior lighting as
a function of certain lighting-relevant states, in which the
respective turning-on or turning-off process takes place with
dimming. The dimming parameters, such as turning-on or turning-off
dimming time or desired final brightness, are selected in advance
as a function of the vehicle state that activated the control
process, which permits a highly variable and situation-specific
lighting control. The lighting control unit, depending on signals
from a sensor group and according to a program stored in a program
memory, controls a lighting device through a controllable
switch.
Inventors: |
Andres; Rudolf (Sindelfingen,
DE), Staehle; Armin (Nufringen, DE),
Mickeler; Reinhold (Altdorf, DE), Petri; Volker
(Aidlingen, DE), Grickscheit; Helmut (Sindelfingen,
DE), Forstner; Benno (Weil der Stadt, DE),
Freerichs; Dieter (Ostelsheim, DE) |
Assignee: |
Mercedes-Benz AG (Stuttgart,
DE)
|
Family
ID: |
6497378 |
Appl.
No.: |
08/553,190 |
Filed: |
November 7, 1995 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
Issue Date |
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302983 |
Sep 12, 1994 |
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Foreign Application Priority Data
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Sep 10, 1993 [DE] |
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43 30 721.3 |
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Current U.S.
Class: |
315/77; 315/316;
315/324 |
Current CPC
Class: |
B60Q
3/80 (20170201) |
Current International
Class: |
B60Q
3/02 (20060101); B60Q 3/00 (20060101); B60Q
001/02 () |
Field of
Search: |
;315/77,291,292,307,316,324 |
References Cited
[Referenced By]
U.S. Patent Documents
Foreign Patent Documents
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3125610 |
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Jan 1983 |
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DE |
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3309548C2 |
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Sep 1984 |
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DE |
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3620861A1 |
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Dec 1987 |
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DE |
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4131425A1 |
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Apr 1992 |
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DE |
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4212361 |
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Mar 1993 |
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DE |
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4235826 |
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Apr 1993 |
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DE |
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Primary Examiner: Pascal; Robert
Assistant Examiner: Shingleton; Michael
Attorney, Agent or Firm: Evenson, McKeown, Edwards &
Lenahan, P.L.L.C.
Parent Case Text
This application is a continuation of application Ser. No.
08/302,983, filed on Sep. 12, 1994 now abandoned.
Claims
What is claimed is:
1. Method for controlling vehicle interior lighting, comprising the
steps of:
determining each of a plurality of lighting-relevant vehicle states
by interrogating at least one state condition that can be
interrogated;
monitoring the vehicle states and if one of the vehicle states is
detected, activating a corresponding control process to turn the
interior lighting on or off;
wherein the corresponding control processes to turn the interior
lighting on or off each include a respective dimming process,
wherein a lighting brightness during a certain time interval is
variably set to a range between a maximum brightness and a zero
brightness for each vehicle state, said respective dimming process
for each vehicle state being determined by corresponding dimming
parameters for each vehicle state, and includes variably setting
values of said dimming parameters as a function of the vehicle
state that is detected and that activates the corresponding control
process.
2. Method according to claim 1, wherein at least one of the vehicle
states is determined by a chain of several state conditions that
are interrogatable and exists only when all of the chain of several
state conditions are met.
3. Method according to claim 2, wherein the control process for
turning off the interior lighting includes setting in advance a
shutoff dimming time as a function of the state of the vehicle as a
dimming parameter.
4. Method according to claim 1, wherein the control process sets a
delay time as a function of the vehicle state to switch off the
interior lighting as a dimming parameter, said delay time delaying
beginning of the dimming process.
5. Method according to claim 1, further comprising setting a
turn-on dimming time and final brightness for the control process
to turn on the interior lighting as a dimming parameter.
6. Method according to claim 1, wherein the lighting-relevant
vehicle states are assigned a priority sequence relative to the
activation of an interior lighting control process, such that if a
higher priority lighting-relevant vehicle state exists, the
corresponding interior lighting control process is activated and
any previously activated control process is interrupted.
7. Method according to claim 2, wherein a state condition for each
of the lighting-relevant states consists in the measured vehicle
interior brightness being below a preset limit.
8. Device for controlling vehicle interior lighting,
comprising:
a central lighting control unit with a program memory, said control
unit including:
means for determining each of a plurality of lighting-relevant
vehicle states by interrogating at least one state condition that
can be interrogated;
means for monitoring the vehicle states;
means for activating a corresponding control process if one of the
vehicle states is detected to turn the interior lighting on or off,
wherein the corresponding control processes to turn the interior
lighting on or off each include respective dimming process, said
activating means including means for variably setting a lighting
brightness for each respective dimming process during a certain
time interval to a range between a maximum brightness and a zero
brightness, said dimming process for each vehicle state being
determined by corresponding dimming parameters, and including means
for variably setting values of said dimming parameters as a
function of the vehicle state that is detected and that activates
the corresponding control process;
wherein said means for detecting includes a sensor group coupled to
the central lighting control unit, the sensor group interrogating
the state conditions for the lighting-relevant vehicle states, and
producing output signals that are fed to the central lighting
control unit;
a lighting device coupled to the central lighting control unit;
and
a switch coupled between the central lighting control unit and the
lighting device, and is controllable by the central lighting
control unit for activating and deactivating the lighting
device.
9. Device according to claim 8, further comprising a brightness
sensor forming a part of the lighting device and being coupled to
the control unit, said brightness sensor detecting vehicle interior
brightness, the central lighting control unit providing an output
signal that serves as information for controlling the switch.
10. Device according to claim 9, further comprising a bright/dark
signal evaluation unit coupled to the brightness sensor and to the
central lighting control unit, the bright/dark signal evaluation
unit receiving the signal from the brightness sensor, and includes
means for adjusting a brightness limit and means for generating a
digital brightness signal that is supplied to the central lighting
control unit.
Description
BACKGROUND AND SUMMARY OF THE INVENTION
The present invention relates to a device and a method for
controlling vehicle interior lighting, in which a plurality of
lighting-relevant vehicle states each determined by at least one
state condition that can be interrogated, is monitored and if the
existence of one of the vehicle states is detected, a corresponding
control process to turn the interior lighting on or off is
activated.
A vehicle interior lighting is known from German Patent Document 36
20 861 A1 which monitors the position of the vehicle doors as a
vehicle state relevant to illumination, and turns on the interior
lighting when a door is opened and turns it off on a time-delayed
basis when the door is closed, by gradually extinguishing the bulb.
The time-delayed shutoff means that the vehicle occupants, even in
darkness, can readily perform the actions required to begin
driving, for example putting on the safety belt, inserting the
ignition key, etc. by means of the interior lighting which is still
active. A similar procedure in which the lighting is initially
reduced by a certain amount when the door is closed, then remains
constant, and finally is dimmed linearly, is disclosed in U.S. Pat.
No. 4,866,345.
German Patent Document 33 09 548 C2 describes a vehicle interior
lighting control in which a vehicle state is monitored that is
governed by two conditions, namely an open or closed vehicle door
and the ignition being off or on. When closing of the door is
detected, the interior lighting is turned off with a time delay.
This also takes place when an open door and an "off" ignition are
detected, preventing unnecessary activation of the interior
illumination if the vehicle door is accidently left open, while
when the door is open and the ignition is on, the interior lighting
remains activated.
In an interior lighting system according to German Patent Document
41 31 425 A1, an entry light, a foot area light, and a seat light
on the vehicle ceiling are provided which, when opening of the
corresponding vehicle door is detected, are switched on in the
direction of entry with a brightness that increases from light to
light, producing an increase in brightness from the road and the
door sill across the floor to the seat.
An object of the present invention is to provide a method and a
device for controlling the vehicle interior lighting that has a
comfortable vehicle interior lighting control that is optimally
adapted to the respective situation, with simultaneously low
construction cost.
This and other objects are achieved by the present invention which
provides a method for controlling vehicle interior lighting,
comprising the steps of: determining each of a plurality of
lighting-relevant vehicle states by interrogating at least one
state condition that can be interrogated; monitoring the vehicle
states and if one of the vehicle states is detected, activating a
corresponding control process to turn the interior lighting on or
off; wherein the corresponding control processes to turn the
interior lighting on or off include respective dimming processes,
and includes setting dimming parameters which determine the dimming
processes, said dimming parameters being set as a function of the
vehicle state that is detected and that activates the corresponding
control process.
The objects are also achieved by a device constructed in accordance
with the present invention and comprises: a central lighting
control unit with a program memory containing a program pattern of
the method of the invention; a sensor group coupled to the central
lighting control unit, the sensor group interrogating the state
conditions for the lighting-relevant vehicle states, and producing
output signals that are fed to the central lighting control unit; a
lighting device coupled to the central lighting control unit; and a
switch coupled between the central lighting control unit and the
lighting device, and is controllable by the central lighting
control unit for activating and deactivating the lighting
device.
The method of the invention takes into account not only one vehicle
state, characterized for example by the opening or closing of a
vehicle door, but several such lighting-relevant vehicle states
established by one or more state conditions that can be
interrogated, for example the state of the ignition, central
locking, and a glow plug preheater as well as the position of the
ignition key. With presettable dimming parameters adjusted to the
detected vehicle state, the method then activates a dimming process
to turn on or turn off the vehicle interior lighting, with the
dimming process being adjustable in a highly variable fashion to
the current situation. Provision of a central lighting control unit
for the plurality of control functions of the method, whose pattern
is stored in a program memory, and by which the controllable switch
is controlled, entails only low construction cost.
In certain embodiments of the invention, a lighting-relevant
vehicle state includes a chain of several state conditions, which
must all be present before lighting control activation takes place.
For example, a vehicle state of this kind can consist of the linked
conditions of an ignition in the "on" position, an open vehicle
door, and the undershooting of a certain boundary value for the
measured vehicle interior brightness. Such an improvement makes it
possible, when a certain state condition exists, for example an
open vehicle door, for different lighting activities to be
performed nonetheless as a function of other interrogated state
conditions.
Certain embodiments of the invention allow the possibility of
turning off the interior lighting depending on the situation, at
different rates by a suitable choice of a corresponding shutoff
dimming time. In addition, with certain other embodiments, a delay
in the start of dimming that depends upon the vehicle state can be
achieved for switching off the illumination.
In certain preferred embodiments, for controlled switching-on of
the interior lighting as a function of the state of the vehicle,
the situation-dependent setting of the turning-on dimming time as
well as the resultant final brightness are provided as dimming
parameters.
In certain embodiments of the invention, the illumination-relevant
vehicle states are ranked so that if a vehicle higher-priority
state exists, the corresponding interior lighting control process
is activated, for example after interruption of a corresponding
control process for a vehicle state of lower priority.
Embodiments of the invention provide that, as a condition inherent
to each of the lighting-relevant vehicle states, an interrogation
is performed to determine whether the measured vehicle interior
brightness is below a preselected limit. This is intended to
prevent the vehicle interior lighting being activated unnecessarily
in daylight, if another state condition of the respective
lighting-relevant vehicle state, for example opening or closing a
door, is fulfilled.
Certain embodiments allow the use of vehicle interior brightness as
a state condition for the control process that can be interrogated,
preferably in the form of a digital, especially a two-valued,
bright/dark signal.
The use of only a single connecting lead both for controlling the
lighting device and for transmitting the brightness sensor signal
in certain embodiments keeps the construction cost low, and also
reduces the number of leads that have to be run in the vehicle.
Other objects, advantages and novel features of the present
invention will become apparent from the following detailed
description of the invention when considered in conjunction with
the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
FIG. 1 is a block diagram of a device constructed in accordance
with the present invention for controlling the interior lighting of
a motor vehicle with a diesel engine.
FIGS. 2A to 2C show corresponding portions of the program flow
chart, according to which the control device of FIG. 1
operates.
FIG. 3 show two flowcharts for two subprograms used in FIGS. 2A to
2C.
DETAILED DESCRIPTION OF THE DRAWINGS
The device according to the embodiment of FIG. 1 contains a central
lighting control unit (1), of which a program memory module (9), a
digital input group (11), a bright/dark recognition stage (8) with
a digital input, and a switch control part (12) are shown
explicitly. In certain embodiments, the control unit (1) also
contains an A/D converter (17) indicated by phantom lines.
Digital input group (11) is connected with signals of a group (10)
of sensors that are independent of one another. Each sensor of this
group (10) checks for the presence of a certain state condition.
Thus, sensors are provided for detecting the open or closed state
of the vehicle doors, for detecting whether the ignition is on or
off, for monitoring whether the ignition key has been inserted or
withdrawn, for monitoring whether a central locking system is
locked or open, and for detecting whether glow-plug warmup is
taking place in a diesel-powered vehicle. An additional sensor unit
(10') is indicated by dashed lines to symbolize that additional
sensors may be required.
From the area of lighting control unit (1) a connecting lead (5)
runs to a lighting unit (2) for the vehicle interior, which has a
bulb (4) as a lighting device. Bulb (4) is grounded through a diode
(16) at one terminal. The other terminal of lamp (4) is connected
to one end of lead (5) and to an onboard system connector (+12 V)
through a manually operable switch (14). When switch (14) is closed
manually, bulb (4) is switched on in any case, independently of
control-induced activation.
A brightness sensor (3) in the form of a photosensitive resistor is
provided in lighting unit (2). Brightness sensor (3) is wired in
series with another diode (15) parallel to bulb (4) and its diode
(16), with the two diodes (15, 16) being polarized in such fashion
that diode (15) associated with brightness sensor (3) does not
conduct when manual switch (14) is closed, while diode (16)
associated with bulb (4) conducts.
The other end of lead (5) runs to a connecting node (18) connected
through a resistor (19) with a negative auxiliary voltage source
(-5 V) and through a switch (6) controllable by lighting control
unit (1) with the onboard electrical system (+12 V). When
controllable switch (6) is opened, resistor (19) and photosensitive
resistor (3) form a voltage divider between ground and the negative
auxiliary voltage (-5 V), with diode (15) polarized in the
conducting direction and associated with brightness sensor (3).
Hence, an analog voltage can be tapped off at connecting node (18)
in this case, the level of said voltage being a measure of the
vehicle interior brightness measured by photosensitive resistor
(3). This analog voltage signal is fed to a bright/dark signal
evaluation unit (7), which converts it into a digital two-valued
bright/dark signal with a specified brightness limit, for which
purpose an inverting amplifier and connected comparator are
provided for example. The brightness limit can be adjusted by a
potentiometer (13) on bright/dark signal evaluation unit (7). The
digital brightness signal from bright/dark signal evaluation unit
(7) is then fed to the input of the bright/dark recognition stage
(8) of lighting control unit (1).
If lighting control unit (1) is equipped with the A/D converter
(17), the bright/dark signal evaluation unit (7) can be an
inverting amplifier, that instead of digital evaluation, or
optionally switchably, delivers the analog voltage signal with
analog amplification to A/D converter (17) of control unit (1). The
brightness limit is then set in central control unit (1), stored
for example in program memory (9). In this case, the lighting
control unit (1) can use the analog brightness signal supplied to
it for additional functions as well, without it already being
digitized. As the dashed area shows, in certain embodiments one or
more sensors in sensor group (10) are provided, which deliver an
analog sensor signal, and connect the signal to A/D converter
(17).
Central lighting control unit (1) evaluates the condition-seeking
signals from sensor group (10) arriving at digital input group (11)
as well as the brightness signal applied to bright/dark recognition
stage (8) or A/D converter (17), according to a program stored in
program memory (9), and then controls, in a manner likewise
determined by this program, controllable switch (6) through switch
control element (12). Closing controllable switch (6) connects one
terminal of bulb (4) through connecting lead (5) to the onboard
electrical system (+12 V), so that bulb (4) is switched on. By
pulsed switching on and off of controllable switch (6), this switch
comprising for example a MOS field effect transistor, the
brightness and the brightness pattern over time can be set as
desired to provide a specific dimming function using the ratio of
the "on" time to the total time of a pulse as well as a suitable
time change in this ratio by pulse width modulation. To avoid
flickering, the switching frequency should be greater than
approximately 60 Hz.
The process stored in program memory (9) of central lighting
control unit (1), according to which dimmed lamp control always
takes place as a function of the various state conditions that
exist and are interrogated, will now be described in detail with
reference to FIGS. 2A to 2C as well as FIG. 3. FIGS. 2A to 2C show
respective parts of the entire program flow that are joined
together at points (A) and (B) indicated.
Beginning with the start of the program shown at the top in FIG.
2A, the process branches depending on five mutually independent
vehicle states (F1 to F5), established by a plurality of state
conditions that can be interrogated.
The first vehicle state (F1) is characterized by an open vehicle
door and low interior brightness, i.e. undershooting of the
established brightness limit. This part of the program, shown on
the left in FIG. 2A, serves to ensure that the interior lighting
remains dimmed during darkness when a vehicle door is already open
or has just been opened.
In an interrogation step (20), a check is initially made to
determine whether a door has been opened. If this is the case, in
an additional interrogation step (21) an interrogation is conducted
to determine whether a brightness measurement performed with
controllable switch (6) open produces undershooting of the preset
brightness limit. If it is, in further successive steps (22, 23) a
corresponding switching-on dimming time (tdon2) as well as a
corresponding desired final brightness (He2) are determined whose
values are stored specifically for this vehicle state in the stored
program. Then a lamp turn-on subprogram step (24) takes place,
which is shown in more detail in the upper half of FIG. 3. After
the subprogram is started in step (25), in the next step (26) the
existing actual brightness (Hi) is detected and transmitted to
central lighting control unit (1), preferably, instead of providing
an additional brightness sensor, by the above-described optional
analog signal evaluation of the signal from the already existing
brightness sensor (3), for example by providing a switching
capability controllable by the lighting control unit (1) between
digital and analog signal evaluation in bright/dark signal
evaluation unit (7). Control unit (1), by the above-mentioned
selection of the blanking conditions of controllable switch (6), as
well as its change over time, controls the subsequent dimming
process in step (27) for dimmed activation of bulb (4) to change
the actual brightness (Hi) to the desired final brightness (He2)
desired for this vehicle state (F1) (i.e. x=2 in step (27))
according to a preprogrammed characteristic curve. For example, the
characteristic curve consists of an increase in brightness that is
linear as a function of time, but it is understood that lamp
activation alternatively can take place according to another
desired characteristic curve.
If a vehicle interior brightness that is above the brightness limit
is detected in interrogation step (21), an additional interrogation
step (28) follows to determine whether bulb (4) is already switched
on, e.g. by interrogating the state of controllable switch (6), and
therefore whether this limit has been exceeded. If bulb (4) is not
switched on, it follows that the brightness limit has been exceeded
by the ambient brightness. In this case, unnecessary illumination
activation is suppressed and the program returns to the first
interrogation step (20). If bulb (4) is switched on, however, for
example by a previous switching-on dimming process, the already
described dimming process will likewise be performed so that bulb
(4) lights and the final brightness value (He2) desired, results.
The additional inquiry as to whether bulb (4) is switched on, if
exceeding of a preset brightness limit was recognized earlier, is
desirable in particular because brightness sensor (3) is integrated
into lighting unit (2) and consequently is significantly influenced
by the brightness of the bulb, making it possible to dim the bulb
(4) to lower light intensity if it is shining too brightly for the
given vehicle state.
The second lighting-relevant vehicle state test (F2) consists of
the two state conditions to be interrogated whether central locking
has been opened and only a small amount of brightness is available.
The part of the program shown in the right-hand half of FIG. 2A
serves to turn on interior lighting in darkness, variably dimmed
for a certain space of time, when central locking is open, and to
turn off the interior lighting after dimming following expiration
of a preset time delay.
In detail, in the corresponding part of the program shown in the
right-hand half of FIG. 2A, a check is performed in a first
interrogation step (29) to determine whether central locking has
been changed from its locked to its open state. If this is the
case, interrogation step (21) is performed once more to determine
whether the interior brightness is below the preselected brightness
limit. If the answer is yes, the following steps (30, 31) are then
performed to determine a turn-on dimming time (tdon1) as well as
desired final brightness (He1). As described with reference to the
program part for the first vehicle state (F1), this continuation of
the program is selected if brightness above the limit is detected,
but interior lighting that had been switched on was detected
simultaneously in the following interrogation step (28). It should
be noted that the values thus established for the switching-on
dimming time (tdon1) and the final brightness (He1) are preset,
adjusted to the second vehicle state (F2), and accordingly can
differ, especially from the other vehicle states, for example the
switching-on time (tdon2) described above and the final brightness
(He2) of the first vehicle state (F1). Then a lamp turn-on
subprogram (24a) is performed which corresponds in its steps to
that for the first vehicle state (F1), with only the possibly
changed input parameters of the duration of the switching-on
dimming process (tdon1) and the final brightness (He1) and, if
necessary, possibly also the switching-on characteristic, i.e. the
time curve of the change in brightness. At the same time, in a step
(32), a delay time (t1) is fixed whose expiration is detected in a
subsequent interrogation step (33). Then, in a step (34), a
turn-off dimming time (tdoff1) is established and with this dimming
parameter, a subprogram is performed for switching off lamp (4)
with dimming in step (35).
This subprogram step (35) is shown in more detail in the lower half
of FIG. 3. Following the start of this subprogram, the actual
brightness (Hi) in the vehicle interior is determined once more.
Central lighting control unit (1) switches lamp (4) by appropriate
control of switch (6) with an adjustable desired time pattern with
dimming down to zero from the actual brightness (Hi), which in this
case corresponds to the final brightness (He1) set before and
therefore needs nothing extra to be measured to determine it. Once
again the time pattern of this shutoff dimming process is variably
adjustable, for example according to a linear, exponential, or
logarithmic curve.
The third illumination-relevant vehicle state (F3) incorporates the
conditions that can be interrogated, whether the ignition key has
been withdrawn and the brightness is below the preselected
brightness limit. This part of the program shown at the left in
FIG. 2B serves to turn on the internal illumination for a certain
period of time, with variable dimming, as soon as the ignition key
is withdrawn in darkness. This allows the occupant to perform the
actions necessary before getting out, e.g. releasing the seat belt,
with adequate brightness. After a preset time delay has expired,
the internal lighting is turned off, with variable dimming.
Specifically for this purpose, an interrogation is performed
initially in step (36) to determine whether the ignition key has
been withdrawn. If the answer is yes, then the brightness
interrogation step (21) already described above is performed,
followed by, as described above, in the event of a negative answer,
interrogation step (28) through a switched-on bulb (4). With a
corresponding positive answer, steps (37, 38) to determine the
desired switching-on time (tdon3) desired for this vehicle state
(F3) and the final brightness (He3) are performed. With these
dimming parameters, a lamp switching-on subprogram (24b) is
performed analogously to the corresponding subprogram (24, 24a)
described above. At the same time, in step (39) a delay (t3) is set
whose expiration is checked with recursive interrogation step (40).
If delay time (t3) has expired, in the next step (41) a shutoff
dimming time (tdofff3) is set and a bulb shutoff subprogram (35a)
is performed, which in turn takes place analogously to the
subprogram (35) described in connection with the program part that
belongs to the second vehicle state (F2), whereby of course the
shutoff dimming times and duration of the shutoff dimming process
can again be chosen differently.
The fourth lighting-relevant vehicle state (F4) contains as
conditions that can be interrogated, whether the vehicle doors are
closed and the interior lighting has been turned on in advance. The
part of the program shown in the right half of FIG. 2b serves in
this case to allow the interior lighting to be turned on for a
certain period of time at a certain brightness level and, after an
adjustable time delay has expired, to turn off the light with
variable dimming. For this purpose, in a first interrogation step
(42), the closing of the doors and (if the answer is yes) in a
subsequent interrogation step (43) the fact of bulb (40) being on
is checked. If bulb (4) was not turned on, no lighting control
process is activated. On the other hand, if bulb (40) was turned
on, in successive steps (44, 45) the turn-on dimming time (tdon4)
and final brightness (He4) associated with this vehicle state (F4)
are set. With these dimming parameters, the lamp turn on subprogram
step (24c), as described in greater detail in reference to step
(24), is performed. At the same time a shutoff delay time (t2) is
set in step (46), whose expiration is checked by time expiration
interrogation step (47) which may be performed repeatedly. After
delay time (t2) has expired, in step (48) a shutoff dimming time
(tdoff2) is set and with this dimming parameter a lamp shutoff
subprogram step (35b) is then performed, so that bulb (4) is turned
off with dimming. The shutoff subprogram (35b) again proceeds
analogously to shutoff subprogram (35) described above, whereby
only the dimming parameters, i.e. the shutoff dimming time and the
shutoff dimming characteristic, need to be modified.
The fifth vehicle state (F5) involves the conditions that can be
interrogated, as to whether the ignition has been turned on and a
vehicle door is open. If the answer is yes, a turn-on dimming
process is activated in darkness. On the other hand, if the door is
shut, after the end of a diesel glow-plug warmup an interrogation
is conducted and if the answer is positive, a shutoff dimming
process is triggered. This corresponding part of the program is
shown in FIG. 2C. It serves firstly to illuminate the interior of
the vehicle if the ignition is turned on and the driver's door is
open in darkness. On the other hand, after the ignition is switched
on and the vehicle doors are shut, the possibly activated interior
lighting is turned off with dimming, but only after the glow-plug
warmup is over. As a result the driver can get in, shut the doors,
turn on the ignition, and then initiate the glow-plug warmup and
still be able to perform the necessary additional steps before
starting to drive before the interior lighting is turned off with
dimming, with the lighting still activated, for example to find the
seat belt buckle and put on the safety belt. The interior lighting
then goes out only after the glow-plug warmup is over.
Specifically, in this part of the program, a check is initially
conducted in the first interrogation step (49) to determine whether
the ignition has been turned on. If this is the case, in the next
interrogation step (50) the door state is checked. If the doors are
shut, the program continues with interrogation step (51) after the
glow-plug warmup is over. If this is not yet the case, the program
returns in a loop before interrogation step (49) for the state of
the ignition. However, as soon as the termination of the glow-plug
warmup has been recognized in step (51), in step (52) a
corresponding shutoff dimming time (tdoff4) is set and with this
dimming parameter as well as a preset shutoff dimming
characteristic, a bulb shutoff subprogram step (35c) is again
performed analogous to the one described above.
On the other hand, if in interrogation step (50) for the door state
an open door is found, the brightness interrogation step (42) is
initiated. If the interior brightness is below the preselected
brightness limit, a turn-on dimming process begins, which comprises
of setting a turn-on dimming time (tdon5) in step (53) as well as a
corresponding desired final brightness (He5) in step (54), as well
as the lamp turn-on subprogram (24d) performed with these dimming
parameters, which is performed in a manner analogous to the lamp
turn-on subprogram (24) described above.
The five parts of the program that are parallel to the starting
point of the process, each assigned to one of the lighting-relevant
vehicle states (F1 to F5), is assigned a ranking for its
performance, as indicated in FIGS. 2A to 2C by showing priorities
(P1) to (P5). Here, (P1) represents the highest priority and (P5)
the lowest, between which the other priorities (P2, P3, P4) are
arranged in stages. As soon as the conditions of an
illumination-relevant vehicle state of higher priority exist, the
corresponding part of the program is performed, while a program
that may possibly already be running is interrupted and replaced by
another lighting-relevant vehicle state with a lower priority.
It follows from the above description of the control method for the
interior lighting that a control process for the interior lighting
that is adjusted to a very specific vehicle state can be performed.
In particular, activation of interior lighting takes place with
dimming assuming a turn-on or turn-off dimming time adjusted to the
respective vehicle state, as well as a desired final brightness in
the event of a turning-on process. In addition, the characteristic
which the time pattern of the dimming process follows can be set in
suitable fashion specifically for the respective vehicle state.
Thus for example it is possible to turn on the interior lighting
with maximum bulb brightness when the door is opened in the dark
with the ignition turned off, but to turn on the interior lighting
with a lower brightness when the door is opened with the ignition
turned on, in order not to blind the driver. The latter will happen
when the part of the program for the fifth vehicle state with the
highest priority (P1) is performed, with the corresponding final
brightness (He5) being chosen to be less than the maximum bulb
brightness. On the other hand, if the ignition is turned off when
the door is opened, the part of the program for the first vehicle
state (F1) which has the second highest priority (P2) is performed,
whereupon the desired final brightness (He2) is set the maximum
bulb brightness.
If, as an additional example of the variability of the interior
lighting control method, the door is closed with the ignition
turned off, the part of the program for the fourth vehicle state
(F4) with the third highest priority (P3) is performed, which at
the end leads to a shutoff dimming process. By selecting a
relatively long shutoff dimming time (tdoff2), this dimming can be
performed at a low speed with the ignition turned off. On the other
hand, if the door is shut with the ignition turned on, in order not
to blind the driver, this slow dimming must be interrupted and the
interior lighting turned off very rapidly with dimming after the
glow-plug warmup. This is accomplished by virtue of the fact that
when the ignition is switched on, the part of the program for the
fifth vehicle state (F5), because of its higher priority (P1),
interrupts the part of the program associated with the fourth
vehicle state (F4) and, through interrogation steps (49, 50, and
51), initiates a rapid shutoff dimming process, for which purpose
the corresponding dimming time (tdoff4) is set to a very low
value.
For the individual skilled in the art, a plurality of additional
variations on the method described above and the device described
above for controlling the interior lighting of a vehicle is
possible within the scope of the invention. For example, one or
more of the five lighting-relevant vehicle states for interior
lighting control can be omitted. If a corresponding adverse affect
on comfort is taken into account, bright/dark detection can be
omitted as well, so that the brightness sensor and the processing
of its sensor signal are omitted and lamp control becomes
independent of the existing interior brightness.
Although the invention has been described and illustrated in
detail, it is to be clearly understood that the same is by way of
illustration and example, and is not to be taken by way of
limitation. The spirit and scope of the present invention are to be
limited only by the terms of the appended claims.
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